TW201906718A - Creasing machine, creasing cylinder for the creasing machine and method for creasing sheets - Google Patents

Abstract

The invention relates to a creasing machine having a creasing tool (14, 20, 21), a counter element (22, 23) cooperating with the creasing tool, and a transportation system (10) for advancing sheets (12) through a creasing area between the creasing tool (14, 20, 21) and the counter element (22, 23), the creasing tool having a creasing plate (24) provided with at least one creasing projection (26), characterized in that the creasing projection (26) on the creasing plate is constituted by a plurality of small, plastically deformed areas which merge into each other so as to form the creasing projection (26). The invention also relates to a creasing plate (24) adapted for being used in a creasing machine according to any of the preceding claims, the creasing plate (24) being made from sheet metal and comprising at least one creasing projection (26) formed from a plurality of small, plastically deformed areas which merge into each other so as to form the creasing projection. Further, the invention relates to a method for creasing sheets (12), in particular made from paper, cardboard or foil, comprising the following steps: data regarding folding creases (30) to be applied to the sheet (12) is provided. A control (60) determines if a suitable creasing plate (24) is available in an inventory or if a new creasing plate (24) is to be manufactured. Based on the determination of the control (60), either an existing creasing plate (24) is retrieved from the inventory (62) or a new creasing plate (24) is manufactured by using a punching module (40) for applying a plurality of small deformations to a creasing plate blank (24'), the deformations constituting at least one creasing projection (26). The creasing plate (24) is mounted on a creasing tool (20, 21), and the creasing tool (20, 21) cooperates with a counter element (22, 23) for applying folding creases (30) to sheets (12) advanced through a creasing area between the creasing tool (20, 21) and the counter element (22, 23).

Description

   Creping machine, creping drum for creping machine, and method for creping sheet   

The present invention relates to a creping machine having: a creping tool; a counter element cooperating with the creping tool; and a sheet for advancing a sheet through a creping area between the creping tool and the counter element A conveying system having a corrugating plate having at least one corrugating protrusion. The invention further relates to a corrugating plate suitable for use in the corrugating machine, and a method for corrugating a sheet made especially of a carton, cardboard or foil.

A corrugator is used to create one or more creases in the sheet from which the blank is cut. Each of the creases forms some kind of "hinge" that allows the blanks formed later to be folded at clearly defined locations.

The corrugating machine can be formed as a device or system that is a stand-alone unit or integrated into a larger machine or system such as a printing or finishing machine.

The sheets may be made of cardboard, carton or foil, and these sheets may be provided to the creping machine, either individually or as part of a web, in a continuous manner.

Creases are formed by applying pressure to the sheet regionally. For this purpose, creping knives are known which press the creping knives against the surface of the sheet so as to create creases. It is also known to provide area protrusions on the creping tool, for example, by etching away portions of the creping tool that should not protrude, or by regionally coating a plastic material in a liquid state that is then cured.

The creping tool may be substantially flat and move back and forth in a direction generally perpendicular to the plane in which the sheet extends, or the creping tool may be generally cylindrical and rotated to convey the sheet through Engage the sheet when wrinkled.

A problem with all creping machines is that these creping machines can hardly quickly adapt to the particular pattern of creases to be applied to the sheet. This situation has become more problematic because digital printing allows very rapid changes from one print job to a different print job.

Assuming the creping tool will be manufactured by means of an etching process, it can take several hours before a new creping tool is available. Assuming that the wrinkled protrusion is formed by applying a plastic material to a carrier, depending on the time necessary for curing the plastic material, the manufacturing time may be shorter. However, the life of this wrinkling tool is significantly shorter than that of a wrinkling tool containing an etched steel sheet. In any case, when using a wrinkling machine in conjunction with a digital printing press, the steps to adapt the wrinkling machine to the new wrinkling job are a bottleneck.

An object of the present invention is to provide a creping tool and a creping method, which can quickly change from one creping pattern to another creping pattern.

To achieve this, the present invention provides a wrinkling machine as defined above, which is characterized in that the wrinkling protrusions on the wrinkling plate are composed of a plurality of small plastic deformation regions, the plurality of small plastic deformation regions The deformed regions are fused to each other to form the wrinkled protrusion. In addition, the present invention provides a corrugating plate suitable for use in a corrugating machine of this type, the corrugating plate being formed of a metal sheet and including at least one corrugating protrusion formed of a plurality of small plastic deformation regions, the The plurality of small plastically deformed regions are fused to each other to form the wrinkled protrusion. Finally, the above object is solved by a method for wrinkling a sheet made especially of paper, cardboard or foil, in which information is provided on the folding creases to be applied to the sheet, and A control determines whether a suitable corrugated sheet is available in an inventory or if a new corrugated sheet is to be manufactured. Based on the determination of the control, an existing corrugated sheet is retrieved from the inventory, or a new corrugated sheet is manufactured by using a punch for applying a plurality of small deformations to a corrugated sheet, The deformed portions constitute at least one corrugated protrusion. Finally, the corrugating plate is mounted on a corrugating tool, and the corrugating tool cooperates with an opposing element for applying a folding crease to a crease region that advances through a corrugating area between the corrugating tool and the opposing element Sheet.

The invention is based on the concept of using a metal corrugated plate, in which the corrugated protrusions are formed by a large number of punch strokes, and the individual corrugated protrusions are generated by individual punch strokes. This concept allows two advantages to be achieved. First, the corrugated plate has a long life due to minimal wear at the corrugated protrusions, simply because the corrugated protrusions are made of metal. The strain hardening that must occur during stamping contributes to the abrasion resistance of the corrugated sheet. Second, individual corrugated plates can be quickly manufactured with very little effort by, for example, a turret punch or a coil punch.

According to a preferred embodiment, a stamping module is disposed at the creping machine. There is no need to install a separate press. In fact, a dedicated (smaller) stamping module can be integrated into the machine to form a self-contained creping machine, which does not require any external machinery when it comes to making creping plates.

The stamping module is preferably a turret stamping machine or a coil stamping machine, because these types of machines allow extremely flexible and fast manufacturing of corrugated plates.

Preferably, the stamping module has a punch and a die, and the punch has a round end portion. The rounded end portions help ensure a smooth transition between the individual deformed regions to form a continuous wrinkled protrusion.

Depending on the geometry of the wrinkled protrusions, the rounded end portions have at least one of a large radius and a small radius. A large radius is advantageous for achieving a smooth transition between the individually deformed regions forming the wrinkled protrusion. A small radius is advantageous for forming a corrugated protrusion which terminates with a very small distance from an adjacent corrugated protrusion, or even intersects the adjacent corrugated protrusion.

According to a specific example, the punch extends along a straight line and has a length of about 5 mm to 50 mm measured along the straight line. The longer the punch, the fewer individual strokes required to produce a wrinkle protrusion. However, shorter punches increase flexibility and reduce the force required to deform the corrugated plate.

According to a preferred embodiment, the mold has a recess for receiving material that is plastically deformed by the punch, the recess having at least one lateral open end, and the open end and the circular end portions of the punch One of them overlaps. This geometry of the mold helps to produce wrinkled protrusions that terminate or even merge with each other at a very small distance from each other, because the wrinkled protrusions that have been created can be positioned next to the open end of the mold So that the punch can precisely deform the creped material at a point very close to an existing creped protrusion.

The mold preferably has an outer contour, and the open end of the outer contour adjacent to the recess extends at an angle of less than 90 °, more preferably at an angle of 45 ° relative to the longitudinal direction of the recess. This geometry has the advantage of producing fused corrugated protrusions that extend at an angle of 45 ° relative to each other.

According to a preferred embodiment of the present invention, an elastic ejector is associated with the mold. The ejector helps push plastically deformed material out of the mold. In addition, the ejector prevents the corrugated plate from being scratched by touching the mold.

The elastic ejector may have the form of a plate made of rubber or an elastomer. This board can be cut in a very precise manner by water jet cutting.

Preferably, the ejector surrounds the mold. This allows the elastic ejector to be mounted to the mold by only forming the elastic ejector with a suitable internal contour that fits the external contour of the mold.

According to a preferred embodiment, a treatment system is provided for transferring the finished corrugated sheet from the stamping module to the corrugating tool. This treatment system is beneficial because it allows automated exchange of one corrugated plate to a new corrugated plate.

Preferably, the disposal system has access to an inventory in which "old" corrugated boards are stored. There is therefore no need to make a new corrugated sheet whenever a different blank will be produced (in other words: for each new job). In fact, there is a great opportunity to find suitable corrugated boards in inventory.

The corrugated sheet may have a thickness in a range of 0.2 mm to 0.6 mm. On the one hand, a metal sheet with this thickness has sufficient strength to achieve a long life, and on the other hand, the metal sheet does not require excessive punching pressure.

Preferably, the corrugated plate is made of carbon steel or stainless steel. This material is advantageous with regard to its mechanical strength and also because no problems with corrosion occur.

The corrugated protrusion may have a height of about 0.6 mm to 1.6 mm. More preferably, a value of approximately 1.2 mm can be used, even though this depends on the material to be wrinkled. It has been confirmed that a value of 1.2mm will achieve good results for the carton.

The corrugated protrusion may have a radius at its apex of 0.2 mm to 0.8 mm, more preferably about 0.35 mm to 0.55 mm. These values have proven to be a good compromise between: on the one hand, clear, well-defined creases; on the other hand, the low risk of damaging or otherwise damaging the corrugated sheet material during the manufacturing process.

Preferably, in a cross section, the corrugated protrusion has a width at its bottom of about 1 mm to 3 mm, preferably about 2 mm. This width has an important effect on the crease and is preferably chosen to be smaller for thinner materials, while larger widths are used to wrinkle thicker materials such as corrugated cardboard.

According to a specific example of the present invention, the creping tool is a reciprocating plunger to which the creping plate is mounted. Therefore, the opposing element is preferably a support plate. A reciprocating plunger or piston allows multiple folding creases to be created at the same time on one sheet.

According to a different embodiment of the present invention, the creping tool is a creping roller to which the creping plate is mounted. Therefore, the opposing element is preferably a opposing roller. The creping drum rotates at a peripheral speed corresponding to the speed at which the sheet advances through the creping area. Therefore, the corrugated sheet "rolls" through the surface of the sheet that can be continuously advanced.

According to a preferred embodiment of the present invention, the rollers can be adjusted relative to the plane on which the sheet is conveyed. This adjustment allows changing the wrinkling direction (from above the sheet to below the sheet and vice versa) so that the carton and the corrugated cardboard can be wrinkled on the same machine. The following treatment is sufficient: exchange the rollers having the corrugated plate among the rollers and the rollers having the layer serving as an opposing element to the corrugated plate, and change the rotation axis and sheet conveyance of the two rollers through the Wait for the distance between the planes where the wrinkled areas between the rollers are located.

Preferably, a servo motor is connected to each of the creping drum and the opposite drum. The use of separate drives allows easy adaptation to the different rotational speeds of the drums, which is necessarily the result of the interchangeable functions of the creping drum and the opposite drum.

To detect the position of the sheet passing through the wrinkled area, a sensor is used. The sensor can detect the front end of the sheet, or detect the mark on the sheet. When using a corrugating roller as a crimping tool, the corrugating plate may be a curved plate clamped to one of the corrugating rollers, or the corrugating plate may be a corrugating sleeve clamped to the corrugating roller. Clamping the crepe plate to the crepe drum requires no different workload than clamping the crepe sleeve to the crepe drum. However, manufacturing a corrugated sheet involves less work than manufacturing a corrugated sleeve.

Preferably, the same clamping mechanism is provided on the two rollers. This makes it very easy to change the drum from the creping drum to the relative drum and vice versa.

In order to ensure that the corrugated plate and the elastic layer are evenly clamped to the rollers without the risk of air pockets remaining between the outer surfaces of the rollers and the sleeve clamped to the rollers, the clamping mechanism includes Contains a clamping pin extending into the opening of the corrugated plate. This allows the corrugated plate to be clamped in a very uniform manner.

Preferably, a cam mechanism is provided for moving the clamping pins between a clamping position and a releasing position. This cam mechanism is technically very reliable and can be manually rotated using simple tools, thus avoiding complex mechanisms.

According to a preferred embodiment of the present invention, the opposing element is covered by an elastic layer. Therefore, a "universal" opposing element is formed, which does not necessarily have to be replaced or adapted when a different corrugating plate is mounted to the corrugating tool. In fact, when the corrugated protrusions deform the carton, cardboard or foil, the elastic layer functions in a "mold" manner.

The elastic layer can be made of rubber or an elastomer, so that the elasticity and hardness of the elastic layer can be easily adapted to specific requirements.

In an alternative embodiment, the opposing element is covered by a layer made of a shape memory material. This shape memory material allows the use of an opposite roller similar to a mold, which has a recessed portion as a counterpart of a crimped protrusion on a corrugated plate. The recessed portions can be obtained very conveniently by rotating the two rollers under a condition that the corrugating plate is tightly pressed against the surface of the opposing roller, thereby forming the recessed portions by means of the corrugated protrusions. When the current wrinkling work is completed, these depressions can be "erased" due to the shape memory effect of the material, so that a "new" relative roller with a smooth cylindrical surface can be obtained.

According to a specific example of the present invention, a driving molding is disposed on the creping plate, and the driving molding extends along most of the periphery of the creping drum. The driving molding is selected in terms of height so that the driving molding applies a constant driving force to the sheet material that advances through the wrinkling area between the rollers, thereby ensuring that the sheets are not wrinkled with respect to the wrinkling plate. The protrusions are properly driven.

The drive molding may be formed from a plastically deformed portion of the corrugated plate in a manner similar to the corrugated protrusions, or may be added to the corrugated plate by, for example, a strip of material from an epoxide material. produce. This increases flexibility because the appropriate height, width, and position of the drive molding can be set for each new creping job, and therefore the creping plate can be used.

According to a specific example of the present invention, the corrugated board blanks are pre-cut. Since creping machines usually have dedicated creping tools, flexibility regarding the size of the creping plate is not necessary. In fact, the production time of the corrugated sheet can be reduced by pre-cutting the corrugated sheet blank before it is sent to the stamping module.

The invention will now be described with reference to the drawings. In the drawings, FIG. 1 schematically shows a creping machine together, FIG. 2 schematically shows a specific example of the creping tool used in the creping machine of FIG. 1, and FIG. 3 schematically shows the creping machine used in FIG. 1. A second specific example of a creping tool in a creping machine, FIG. 4 shows a cross-section through a creping plate that is mounted to the creping tool and produces a folding crease by pressing a sheet against an opposing element, Fig. 5 schematically shows a procedure for forming a creping protrusion on a creping plate, Figs. 6a to 6c show three different specific examples of punches used in the creping machine of Fig. 1, and Figs. 7a and 7b show The first specific example of the mold used in the creping machine of FIG. 1, FIG. 8 shows the second specific example of the mold used in the creping machine of FIG. 1, FIG. 9 shows the mold according to the prior art, and FIG. The cross section of the corrugated board blank that passes through the perforation and the mold when deformed. Figures 11a and 11b schematically show the mold of Figures 7a and 7b when two fused corrugated protrusions are produced and the fold crease is folded due to these Protrusions are produced, and Figs. 12a to 12e schematically show Figs. 7a and 7a for making three fusion folded protrusions. The mold and fold creases of FIG. 7b are generated due to these wrinkled protrusions, and the corresponding blanks cut from the sheet and the box made from the blanks. FIGS. 13a and 13b show the use of the punches of FIGS. 6b and 6c in more detail. Figs. 14a and 14b show the obtained crumpled protrusions, and Figs. 14a and 14b show a cross section through the creped protrusions for creping the carton, and Figs. 15a and 15b show the creped protrusions for the corrugated carton in cross section Fig. 16a and Fig. 16b show the creping tool of Fig. 3 under the first condition and the second condition, and Fig. 17 schematically shows the crease in more detail with the rotation speed of the drum. The crumpling tool combined with the control member, FIG. 18 shows a schematic cross-section through the creping tool to explain the rotation speed of the roller, and FIG. 19 shows the two rollers of the creping tool and the sheet to be provided with a crease on a larger scale. 20a to 20c show the top view of the corrugated plate, the cross-section through the corrugation tool with driving molding and the part through the corrugation plate with driving molding and corrugated protrusions. Sectional, Figures 21a to 21c show rolls used in creping tools Perspective view, enlarged view of the clamping mechanism for clamping the corrugated plate, and the elastic layer for clamping the opposite roller, FIGS. 22a to 22g show different steps of using the relative roller according to an alternative embodiment, FIG. 23a Up to FIG. 23d shows the roller used in the creping tool in more detail, and FIGS. 24a and 24b show the relative roller in more detail.

In Fig. 1, a corrugator is schematically shown. The creping machine comprises a conveying system 10 for advancing the sheet 12 through a creping area 14 in which folding creases can be applied to the sheet 12.

Additional processing stations 16, 18 may be provided as part of or associated with the creping machine. The processing stations 16, 18 can be used to cut, fold, glue, or otherwise process the sheet 12 or articles made from sheet material.

The sheet 12 may be made of cardboard, carton, or foil, and the sheets may be processed later to cut the blank from the sheet to form a package, box, wrap, envelope, or similar product.

The sheet 12 may be supplied separately to the creped region 14 as shown in the figure, or in the form of a continuous web guided through the creped region 14.

It is also possible to integrate a cutting system into the corrugated area 14 which allows the separation of individual blanks from the sheet.

In the creping area 14, a creping tool and an opposing element cooperate to apply at least one folding crease to the sheet 12. For this purpose, the corrugating tool is provided with a corrugating plate which is provided with a corrugating protrusion. The geometry and configuration of the corrugated protrusions on the corrugated plate correspond to the folding creases to be applied to the sheet.

A first example of a creping tool and opposing element lane for use in the creping region 14 is shown in FIG. 2.

The creping tool is here in the form of a plunger 20 which can be pushed towards and pressed against the opposing element 22. A corrugated plate 24 having at least one corrugated protrusion 26 is attached to the plunger 20. For added clarity, only a single wrinkle protrusion 26 is shown here.

On the side facing the plunger 20, the opposing element 22 is provided with an elastic layer 28, which is preferably formed of rubber or an elastomer.

The sheet 12 to be provided with a folding crease is advanced with the conveying system 10 so as to be positioned between the plunger 20 and the opposing member 22. Next, the plunger 20 is pressed against the elastic layer 28, and thereby the crumpling protrusion 26 generates a folding fold 30 by deforming the sheet 12 in an area.

A second specific example of a creping tool and an opposing element is shown in FIG. 3. Here, the creping tool is provided in the form of a creping drum 21, and the opposing element is in the form of an opposing drum 23. Therefore, the corrugated plate 24 is curved, and the elastic layer 28 is cylindrical.

A fold crease 30 is generated by advancing the sheet 12 through the gap between the creping drum 21 and the opposing drum 23.

The interaction between the corrugated plate 24 and the sheet 12 is shown in more detail in FIG. 4.

The corrugated protrusions 26 are formed at the corrugated plate 24 by repeatedly and regionally deforming the material of the corrugated plate 24 so as to generate the corrugated protrusions 26 in a desired pattern. In consideration of the desired plastic deformation, the corrugated plate 24 is formed of steel, specifically, carbon steel or stainless steel. The corrugated sheet preferably has a thickness of about 0.2 mm to 0.6 mm.

In order to produce the wrinkled protrusions 26, a stamping module 40, a turret punch or a coil press, is provided. These types of stamping machines are generally known. However, it is preferable to adapt these punches slightly for use in combination with a corrugator. In detail, the stamping module 40 may not be as versatile and powerful as a conventional stamping machine, because the stamping module must only perform a very limited number of different operations in a relatively thin material (i.e., produce substantially Linear wrinkled protrusions).

A stamping module 40 is schematically shown in FIG. 1, wherein a punch 42 is used to plastically deform the corrugated sheet blank 24 ′.

In addition, the stamping module 40 includes a turret 44 in which a plurality of different punches 42 are stored.

FIG. 5 schematically shows how the stamping module 40 generates the creped protrusions 26 by repeatedly plastically deforming the creped plate blank 24 '. The punch 42 is shown with a solid line in cooperation with a die 46 positioned on the opposite side of the corrugated sheet blank 24 '. The position of the punch 42 during the previous punching stroke is shown with a dotted line, and the dotted line indicates the position of the punch 42 during the punching stroke that is continued again.

Each stroke produces a small plastic deformation region at the corrugated slab blank 24 ', and all of these plastic deformation regions form a corrugated protrusion 26.

6a to 6c show different specific examples of the punches arranged on the carrier 43.

In Fig. 6a, a punch 42 having a relatively short projection 45 is shown. The length of the protruding portion may be about one centimeter.

A relatively small radius is provided at the ends of the protruding portions that are opposed to each other when viewed in the longitudinal direction of the protruding portion 45. These radii may be about 0.2 mm to 2 mm.

In Fig. 6b, a punch 42 is shown, wherein the protruding portion 45 is approximately three times the length of the protruding portion 45 of the punch 42 shown in Fig. 6a. It can be seen that the radius at the opposite end of the protruding portion is relatively large.

In Fig. 6c, punches 42 are shown which have different radii at opposite ends of the projections 45. There is a small radius R _{1 of} only about 0.2 mm to 2 mm, and there is a large radius R ₂ which may be about 2 mm to 15 mm.

The height H (see also FIG. 10) of the protruding portion 45 protruding from the front end surface of the punch 42 is approximately 1 mm to 2 mm.

7a and 7b show a specific example of a mold 46 adapted to cooperate with a punch 42 mounted on a carrier 47.

The die 46 has a support surface 48, during which the corrugated sheet blank 24 'may abut the support surface. Within the support surface 48, a depression 50 is provided. The depressions 50 are sized to receive the plastically deformed material of the corrugated plate blank 24 ′ forming the corrugated protrusions 26.

As can be seen in Figures 7a and 7b, the depressions 50 are open at their opposite ends.

As can further be seen in FIG. 7 a, the outer contour of the die 46 adjacent to one of the open ends of the depression 50 extends obliquely with respect to the longitudinal direction of the depression 50. In detail, the outer contour at each side of the depression 50 extends at an angle of 45 ° with respect to the longitudinal direction of the depression 50.

At the opposite ends of the depression 50, the outer contour of the die 46 extends perpendicularly with respect to the longitudinal direction of the depression 50.

The elastic ejector 58 is disposed at the mold 46. The ejector 58 is formed of rubber or elastomer as a plate and snugly surrounds the mold 46, so that the ejector remains in the position shown in Fig. 7b without any additional measures.

In FIG. 8, a different specific example of the mold 46 is shown. Here, the mold 46 has an inclined profile at both open ends of the depression 50 (see the portion pointed by the arrow P).

In FIG. 9, a conventional mold 46 is shown having a circular support surface 48.

In FIG. 10, a schematic cross-section through a punch 42 cooperating with a die 46 is shown.

During the process of plastically deforming the corrugated sheet blank 24 ′ area to form the corrugated protrusions 26, the corrugated sheet blank is held between the mold 46 and the carrier 43. The carrier 43 is spring-loaded towards the mold 46 in order to function as a clamp.

This avoids tension in the corrugated slab blank 24 ', which may cause undesired deformation.

In FIGS. 11 a and 11 b, it is schematically shown how the adjacent corrugated protrusions 26 can be formed by means of a punch cooperating with the die 46. For better clarity, the punches and corrugated plates are not shown in Figure 11a. Actually, only the corrugated protrusions 26 formed at the corrugated plate 24 are shown.

The wrinkled protrusion 26 extending to the left in FIG. 11a is a previously formed protrusion. The corrugated protrusions 26 extending through the depressions in the die 46 are the corrugated protrusions and punches 42 currently formed. It can be seen that the “new” corrugated protrusion 26 may be formed to a point immediately adjacent to the “old” corrugated protrusion 26.

The results immediately adjacent to the corrugated protrusions 26 are visible in FIG. 11b showing the folded creases 30, which are arranged at a 90 ° angle with respect to each other and almost merge with each other. Since almost no uncreped material remains in the corners between the folded creases 30, extremely precise folding can be achieved in this area.

In Figs. 12a to 12e, it is shown how three corrugated protrusions 26 can be formed at the corrugated plate. Due to the specific contour at one of the open ends of the depressions 50, the three corrugated protrusions 26 may be fused to each other at almost an intersection. As can be seen in FIG. 12 d, such crumpled protrusions 26 may be used to form a fold crease 30 at the sheet 12.

These corrugated protrusions are intended to fold a hook-bottom box or a composite sheet of four corners or hexagonal discs.

The stamping module 40 can generate different corrugated plates 24 by appropriately deforming the corrugated plate blank 24 'at a desired position. The creping machine, and the control member 60 shown in detail in the creping machine, is particularly likely to determine whether a new creping plate 24 is to be manufactured or whether it can be used for the previous "Old" corrugated board in wrinkle work. Depending on the determination, the control 60 starts: the stamping module 40 manufactures a new corrugated plate 24, or retrieves the "old" corrugated plate 24 from the stock 62 used to store the previously produced corrugated plate 24.

The corrugating plate 24 (newly manufactured or retrieved from the inventory 62) is taken over by the disposal system 64 and then installed at the corrugating tool.

If the creping tool is a punch, the plate is mounted in a flat shape. If the creping tool is a creping drum, the creping plate 24 may be bent and clamped to the creping drum 23 or may form a creping sleeve that is closed circumferentially, which may then be mounted to the creping drum 23.

As explained above, a punch having a larger radius at the opposite side (to be precise: a larger radius at the opposite side of the protruding portion 45) is used to obtain a material having a material deformed with each stroke of the punch The smooth transition between the wrinkled protrusions 26. Fig. 13a shows the corrugated protrusions 26 terminating at a large distance from each other. The corrugated protrusions 26 merge into the corrugated plate 24 very smoothly.

Fig. 13b shows two corrugated protrusions 26 terminating at a minimum distance from each other so as to almost merge with each other. These corrugated protrusions 26 are obtained by using a punch 42 having a small radius at least at its "forward" end (refer to the direction in which the corrugated sheet blank 24 'is displaced during a continuous stroke). The small radius allows the corrugation protrusion 26 to rise relatively sharply from the corrugation plate 24, so that a small distance between adjacent ends of the corrugation protrusion 26 is possible.

It can be seen that the ends of the wrinkled protrusions at the opposite ends terminate with a larger radius.

Figures 14a and 14b show a cross-section through the corrugated protrusions 26, which have been proven to be very effective in corrugating the carton.

In Fig. 14a, the corrugated plate has a thickness in the range of 0.4 mm, and the height h of the corrugated protrusion is in the range of 0.6 mm to 1.6 mm.

Depending on the specific carton to be wrinkled, the radius R at the apex of the wrinkled protrusion 26 may be in the range of 0.25 mm to 0.7 mm. In other words, the vertex matches an inscribed circle with a diameter of 2R.

The preferred value of the height h is about 1.2 mm, and the preferred radii can be 0.35 mm and 0.525 mm.

In Fig. 15a, a corrugated protrusion 26 for corrugating a corrugated cardboard is shown. It can be seen that compared to the cross-sections shown in Figs. 14a and 14b, a much wider wrinkled protrusion is used. Specifically, the angle α is larger than 90 °. According to a preferred embodiment, the angle may be in a range of 110 ° to 120 °, and particularly 114 °.

The wider conical shape of the cross section of the corrugated protrusion 26 is effective for compressing the carton on each side of the crease to form the space necessary for folding corrugated cardboard (due to the increased thickness of the corrugated cardboard), thereby reducing the The tension generated by the box.

In addition, the typical height of the wrinkled protrusions 26 is about 1.2 mm. As the radius R at the apex of the cross section, a value of about 0.5 mm to 0.6 mm is suitable, particularly 0.53 mm.

As a radius R at the bottom of the wrinkled protrusion 26, a value of about 0.5 mm has proven to be beneficial.

In addition, the inscribed circle may have a diameter of 1.05 mm.

Notably, the corrugated protrusions 26 on the same corrugated plate 24 may have different heights according to specific requirements.

Figures 16a and 16b show an advantageous aspect of the creping tool.

When the creping of the cardboard is changed to the creping of the corrugated carton, the creping direction needs to be changed. This change can be easily achieved by changing the functions of the two rollers 21,23.

In FIG. 16 a, the upper roller acts as the opposing roller 23 and the lower roller is the creping roller 21. Therefore, the elastic layer 28 is attached to the upper drum, and the corrugated plate 24 is attached to the lower drum.

In the configuration shown in Figure 16b, this configuration is reversed. The elastic layer 28 is attached to the lower drum, and the corrugated plate 24 is attached to the upper drum. Therefore, the upper roller functions as the creping roller 21 and the lower roller functions as the counter roller 23.

However, the same roller set was used. The function of the roller will only be determined by the "tool" (creping plate 24 or elastic layer 28) mounted to it. Therefore, both rollers are provided with the same clamping mechanism (indicated here very briefly by the element symbol 60) and the rollers have the same diameter.

The functional outer radius of the two rollers depends on the tool mounted to the rollers. In detail, the external radius of the function of the roller provided with the elastic layer 28 is larger than that of the roller provided with the corrugated plate 24. Therefore, the plane on which the sheet 12 advances through the wrinkled area between the rollers must be adjusted depending on the specific configuration. The differences Δ between Figs. 16a and 16b are indicated.

The vertical adjustment of the plane on which the sheet 12 is provided can be obtained by vertically adjusting the feeding device that advances the sheet or by vertically adjusting the two rollers 21, 23 with respect to the feeding plane.

Another consequence of the different functional radii of the two rollers is that the rotation speeds of the rollers are slightly different, because the tangential velocity at the meshing point at the sheet 12 must be the same. In addition, the rotation speed must match the speed at which the sheet 12 is advanced through the creping tool.

In consideration of the individual control of the rotation speed, each drum is provided with a servo motor 62 controlled by means of a machine control 64. Signals related to the position of the clamping device 60 are also provided to the machine control 64 because these clamping devices form dead zones that can be formed without wrinkles.

In addition, the machine control 64 is provided with a signal related to the position of advancement through 12 of the wrinkling tool. This signal can be obtained via a sensor 66, which detects, for example, the leading edge of the sheet 12 upstream of the creping tool.

Based on the effective radius R _E , the speed V at which the sheet 12 advances through the creping tool, and the signal from the sensor 66, the machine control 64 suitably controls the servo motor 62 so as to achieve an appropriate rotation speed for each of the rollers U also achieves the correct position of the dead zone relative to the individual sheets.

In order to manufacture the corrugated plate 24, it must be remembered that the corrugated plate blank 24 'is deformed when it is in a flat shape, and the corrugated plate is installed in a curved shape when it is installed on the corrugated drum 21. This causes the creping protrusions 26 to have a distance from each other when the creping plate is mounted to the creping drum 21, which is greater than the distance in the flat configuration of the creping plate.

As can be seen in FIGS. 18 and 19, the creping protrusion 26 is pressed into the carton to be creped at a certain distance (for example, 1 mm), however, the distance is smaller than the total height of the creping protrusion. However, preferably, the outer surface of the corrugated plate 24 does not touch the upper surface of the sheet 12. Therefore, a gap exists between the outer surface of the corrugated plate 24 and the upper surface of the sheet 12.

FIG. 18 shows a linear actual length L between two creases 30 in an example, which is measured parallel to the feeding direction of the sheet 12. The actual bending the same length between the top of a corresponding corrugated projection 26 may have a function of measuring the effective radius R _E L. It can be seen that, under the unfolded flat condition of the corrugated plate 24, the unrolled length L _{D is} smaller than the actual length L due to the difference between the unrolled radius R _D and the functional effective radius R _E. Therefore, the two corrugated protrusions 26 must be formed on the corrugated plate 24 at a distance parallel to the feeding direction, which distance is smaller than the actual distance that each crease should have on the sheet 12.

In Figs. 20a and 20b, another aspect of the creping tool is shown.

Generally, the sheet 12 is driven between the creping roller 21 and the opposing roller 23 due to the contact of the creping protrusion 26 with the sheet and also due to the contact of the sheet with the opposing roller. However, there is a wrinkled configuration in which the wrinkle-free protrusion 26 engages the sheet 12 at a certain point in time. Due to the gap G explained with reference to FIGS. 18 and 19, no appropriate driving force can be applied to the sheet 12 at these time points.

In order to ensure that the sheet 12 is always driven positively regardless of the specific position of the creping protrusion 26, a driving bead 27 is provided which extends in a circular direction along the entire creping plate 24. The driving molding 27 may be a plastic deformed portion of the corrugated plate 24 in the same manner as the corrugated protrusion 26.

However, it is also possible to form the drive molding 27 in different ways. As an example, epoxy moldings can be added to the corrugated board in a separate manufacturing operation. This drive molding can be seen in Figure 20c.

The drive molding 27 does not have to protrude from the surface of the corrugated plate 24 in such a manner as to form a distinct crease in the sheet 12. The height can be selected mainly in view of the expected driving force that should be generated.

21a to 21c show the clamping mechanism 60 in more detail.

The clamping mechanism 60 is effective for anchoring both ends of the corrugated plate 24 or the elastic layer 28 and pushing the two ends equally toward each other. This ensures that the individual sleeves are correctly positioned around the drum. In addition, this avoids the problem of airbags remaining under the cannula. When the respective sleeves are under pressure during operation, these air bags may cause damage to the corrugated plate 24 or the elastic layer 28.

22a to 22g show an additional aspect of the creping machine.

In this specific example, a sleeve of a shape memory material 29 is used on the opposite roller 23 instead of the elastic layer 28. The shape memory material layer 29 is plastically deformed by the corrugated plate 24.

In Fig. 22a, the corrugating plate 24 has been mounted to the corrugating drum 21, and the layer 29 having a flat surface under the initial conditions is mounted to the opposing drum 23.

In order to shape the layer 29, the two rollers 21, 23 are advanced toward each other so that the protrusions 26 on the corrugated plate 24 penetrate into the layer 29 (see FIG. 22b).

After increasing the distance between the rollers 21, 23 (and, if necessary, after curing), the layer 29 has the shape of the opposing mold of the corrugated plate 24 (see Fig. 22c).

Subsequently, a creping roller 21 having a creping plate 24 and an opposing roller 23 having a layer 29 can be used to crepe the sheet 12 (see FIG. 22d).

After a wrinkle job has been completed, the layer 29 returns to its original condition. For this purpose, the layer 29 may be heated (indicated schematically by the element symbol H in Figs. 22e and 22f) so that the recessed portions in the layer 29 are "erased".

When the layer 29 has returned to its original flat shape (see Fig. 22g), the wrinkling machine is ready for the next wrinkle job, which is formed by deforming the layer 29 with a new wrinkle plate 24 A new relative mold begins.

Figure 23a shows the creping drum 21 in more detail.

The clamping mechanism 60 has a clamping pin 62 that is movable between a clamping position (shown in Fig. 23c) and a release position (shown in Fig. 23d).

In the release position, the clamping pins 62 are spread apart compared to the clamping position. Looking at FIGS. 23c and 23d, the distance between the clamping pins 62 in the clamped position is smaller than the distance in the released position. In other words, when the clamping pin is in its clamping position, the corrugating plate 24 having the hole to which the clamping pin 62 is engaged is pulled toward the outer circumference of the corrugating drum.

The clamping pin 62 is mounted to a sliding element 64 which is arranged in a groove 66 formed in the creping drum 21. The sliding elements 64 are biased towards the center of the slot 66 and thus towards each other (and into a clamping position) by means of a spring 68 which is shown schematically.

A release mechanism is provided for moving the clamping pin 62 from the clamping position into the release position. The release mechanism is formed here as a cam mechanism.

The cam mechanism has a plurality of cams 70 which are non-rotatably mounted on the shaft 72. The shaft is rotatably mounted in the groove 66. The cam 70 is symmetrical about the center of the shaft 72. Therefore, the two vertices are separated by 180 °.

The shaft 72 is provided with a hole for receiving an actuating tool 74 which may be a simple rod. The actuation tool 74 allows the shaft and therefore the cam 70 to rotate from the rest position shown in Fig. 23c to the deployed position shown in Fig. 23d.

In the rest position, the cam 70 does not exert a significant force on the sliding elements 64 such that the sliding elements are pushed into each other by the spring 68 into the clamping position.

In the deployed position, the cam pushes the sliding element 64 apart into the released position against the force of the spring 68.

The amount of rotation of the shaft 72 for transferring the cam 70 from the rest position to the extended position is approximately 90 °. It can be seen that in the deployed position, the cam 70 moves "outside" the dead point position. When viewing FIG. 23d, in this dead point position, the two vertices are arranged horizontally, thereby ensuring that the release mechanism is reliably maintained in the deployed position While the clamping pin 70 is in the released position.

To install the corrugated plate, the clamping pin 62 is brought to its release position. Next, a corrugating plate is installed at the corrugating drum 21 so that the clamping pins engage into holes provided near the edges of the corrugating plate, which are disposed opposite to each other. Then, the release mechanism is returned to the rest position, so that the clamping pin 62 pulls the corrugating plate 24 along the outer circumference of the corrugating drum by the spring 68.

The clamping pin 62 is in the form of a hook, so there is a minute undercut into which the corrugated plate engages. This ensures that when the creping plate is clamped to the creping drum, it remains mechanically "under the clamping pin 62" and cannot be disengaged axially outwards.

Figures 24a and 24b show the same clamping mechanism 60 different from the creping drum.

The elastic layer 28 has a reinforcing plate 80 having holes 82 into which the clamping pins 62 are engaged.

Claims (40)

    A wrinkling machine having: a wrinkling tool (14, 20, 21); a counter element (22, 23) cooperating with the wrinkling tool; and a sheet (12) for advancing through the wrinkling tool (14, 20, 21) and one conveying system (10) of a wrinkle area between the opposing element (22, 23); the wrinkle tool has a wrinkle plate (at least one wrinkle protrusion) (26) 24); characterized in that the corrugated protrusion (26) on the corrugated plate is composed of a plurality of small plastic deformation regions, and the plurality of small plastic deformed regions are fused with each other to form the corrugated projection (26) ).         The wrinkling machine according to claim 1, wherein a punching module (40) is provided.         The wrinkling machine according to claim 2, wherein the punching module (40) is a turret punching machine or a coil punching machine.         The wrinkling machine according to claim 2 or 3, wherein the punching module (40) has a punch (42) and a die (46), and the punch (42) has a round end portion.         The wrinkling machine according to claim 4, wherein the rounded end portions have at least one of a large radius and a small radius.         The corrugating machine as claimed in claim 4 or 5, wherein the radius at the rounded end portions of the mold is about 0.2 mm to 2 mm or 2 mm to 15 mm.         The corrugating machine according to any one of claims 4 to 6, wherein the punch (42) extends along a straight line and has a length of about 5 mm to 50 mm measured along the straight line.         The wrinkling machine according to any one of claims 4 to 7, wherein the mold (46) has a recess (50) for receiving a material that is plastically deformed by the punch (42), and the recess (50) ) Has at least one lateral open end that coincides with one of the rounded end portions of the punch.         The wrinkling machine according to claim 8, wherein the mold (46) has an outer contour, and the open end of the outer contour adjacent to the recess (50) forms an angle of less than 90 ° with respect to the longitudinal direction of the recess. extend.         The wrinkling machine according to claim 9, wherein the outer contour extends at an angle of 45 ° with respect to the longitudinal direction of the depression (50).         The wrinkling machine according to any one of claims 4 to 10, wherein an elastic ejector (58) is associated with the mold (46).         The creping machine according to claim 11, wherein the elastic ejector (58) is a plate made of rubber or an elastomer.         The wrinkling machine according to claim 11 or 12, wherein the ejector (58) surrounds the mold.         The wrinkling machine according to any one of claims 2 to 13, wherein a treatment system (64) is provided for transferring the finished wrinkle plate (24) from the stamping module (40) to the Wrinkle tool (14).         The wrinkling machine as described in claim 14, wherein one of the stocks (62) is associated with the disposal system.         The corrugating machine according to any one of the preceding claims, wherein the corrugating plate (24) has a thickness in a range of 0.2 mm to 0.6 mm.         The corrugating machine according to any one of the preceding claims, wherein the corrugating plate (24) is made of carbon steel or stainless steel.         The wrinkling machine according to any one of the preceding claims, wherein the wrinkling protrusion (26) has a height (h) of about 0.6 mm to 1.6 mm, particularly about 1.2 mm.         The wrinkling machine according to any one of the preceding claims, wherein the wrinkling protrusion has a radius at its apex of about 0.2 mm to 0.8 mm, particularly about 0.35 mm to 0.55 mm.         The wrinkling machine according to any one of the preceding claims, wherein the wrinkling protrusion has a width at its bottom of one of approximately 1 mm to 3 mm, preferably approximately 2 mm, in a cross section.         The creping machine according to any one of the preceding claims, wherein the creping tool is a reciprocating plunger or piston (20) to which the creping plate (24) is mounted.         The wrinkling machine according to claim 21, wherein the opposing element (22) is a support table.         The wrinkling machine as described in claim 1 to 20, wherein the wrinkling tool is a wrinkling roller (21) to which the wrinkling plate (24) is mounted.         The creping machine according to claim 23, wherein the creping plate (24) is a curved plate clamped to one of the creping drums (21).         The creping machine according to claim 23, wherein the creping plate (24) is a creping sleeve clamped to the creping drum (21).         The creping machine according to any one of claims 23 to 25, wherein the opposing element is an opposing roller (23).         The creping machine according to claim 26, wherein the rollers (21, 23) can be adjusted relative to the plane on which the sheet (12) is conveyed.         The creping machine according to claim 26 or 27, wherein a servo motor (62) is associated to each of the creping drum (21) and the opposite drum (23).         The wrinkling machine according to claim 28, wherein a sensor is provided for detecting the position of the sheet (12).         The wrinkling machine according to any one of claims 27 to 29, wherein an identical clamping mechanism (60) is provided on two rollers (21, 23).         The corrugating machine according to any one of claims 23 to 30, wherein the clamping mechanism (60) includes a clamping pin extending into an opening of the corrugating plate (24).         The wrinkling machine according to claim 31, wherein a cam mechanism is provided for moving the clamping pins between a clamping position and a releasing position.         The wrinkling machine according to any one of the preceding claims, wherein the opposing element is covered by an elastic layer (28).         The wrinkling machine according to claim 33, wherein the elastic layer (28) is made of rubber or an elastomer.         The wrinkling machine according to any one of claims 1 to 32, wherein the opposing element is covered by a layer (29) made of a shape memory material.         The creping machine according to any one of claims 22 to 35, wherein a driving molding (27) is provided on the creping plate (24), and the driving molding is along the creping roller (21). Most of the perimeter extends.         A corrugating machine as claimed in claim 36, wherein the drive molding (27) is added to the corrugating plate (24) and consists, for example, of an epoxide material.         A corrugated plate (24) suitable for use in a corrugating machine according to any one of the preceding claims, the corrugated plate (24) being made of sheet metal and containing a plurality of small plastically deformed regions Forming at least one corrugated protrusion (26), the plurality of small plastic deformation regions are fused to each other to form the corrugated protrusion.         A method for corrugating a sheet (12) made especially of paper, cardboard or foil, the method comprising the steps of providing information on a folding crease (30) to be applied to the sheet (12) A control member (60) determines whether a suitable corrugated board (24) is available in a stock or whether a new corrugated board (24) is to be manufactured, and based on the determination of the control member (60), from the stock (62) Retrieve an existing corrugated sheet (24), or make a new sheet by using a stamping module (40) for applying a plurality of small deformations to a corrugated sheet (24 ') A corrugated plate (24), the deformed portions constitute at least one corrugated protrusion (26), the corrugated plate (24) is mounted on a corrugated tool (20, 21), the corrugated tool (20, 21) Cooperate with a counter element (22, 23) for applying a fold crease (30) to a sheet that advances through a crumple area between the creping tool (20, 21) and the counter element (22, 23)材 (12).         The method of claim 39, wherein the corrugated slab blanks (24 ') are pre-cut.